Double Blind Trials

These activities demonstrate how double blind trials are run, explaining what a placebo is and how the placebo effect works, how bias is removed as far as possible and how participants and trial medicines are randomised.

Curriculum Links

  • KS3: Science
  • KS4: Biology
  • SQA Access, Intermediate and Higher: Biology

Key words

  • double-blind trials
  • observer bias
  • placebo effect
  • placebo
  • randomisation
  • clinical trials
  • designing a fair trial


  • Placebo Effect
  • Observer Bias
  • Double Blind Trial